class CoverImg {
    String? big;
    var height;
    var width;

    CoverImg({this.big, this.height, this.width});

    factory CoverImg.fromJson(Map<String, dynamic> json) {
        return CoverImg(
            big: json['big'], 
            height: json['height'], 
            width: json['width'], 
        );
    }

    Map<String, dynamic> toJson() {
        final Map<String, dynamic> data = new Map<String, dynamic>();
        data['big'] = this.big;
        data['height'] = this.height;
        data['width'] = this.width;
        return data;
    }
}